1 files changed, 62 insertions, 66 deletions

diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c
index 383631873748..642b9d382fb4 100644
--- a/net/netlink/af_netlink.c
+++ b/net/netlink/af_netlink.c
@@ -84,7 +84,7 @@ struct listeners {
 
 static inline int netlink_is_kernel(struct sock *sk)
 {
-	return nlk_sk(sk)->flags & NETLINK_F_KERNEL_SOCKET;
+	return nlk_test_bit(KERNEL_SOCKET, sk);
 }
 
 struct netlink_table *nl_table __read_mostly;
@@ -349,9 +349,7 @@ static void netlink_deliver_tap_kernel(struct sock *dst, struct sock *src,
 
 static void netlink_overrun(struct sock *sk)
 {
-	struct netlink_sock *nlk = nlk_sk(sk);
-
-	if (!(nlk->flags & NETLINK_F_RECV_NO_ENOBUFS)) {
+	if (!nlk_test_bit(RECV_NO_ENOBUFS, sk)) {
 		if (!test_and_set_bit(NETLINK_S_CONGESTED,
 				      &nlk_sk(sk)->state)) {
 			sk->sk_err = ENOBUFS;
@@ -677,6 +675,7 @@ static int netlink_create(struct net *net, struct socket *sock, int protocol,
 	struct netlink_sock *nlk;
 	int (*bind)(struct net *net, int group);
 	void (*unbind)(struct net *net, int group);
+	void (*release)(struct sock *sock, unsigned long *groups);
 	int err = 0;
 
 	sock->state = SS_UNCONNECTED;
@@ -704,6 +703,7 @@ static int netlink_create(struct net *net, struct socket *sock, int protocol,
 	cb_mutex = nl_table[protocol].cb_mutex;
 	bind = nl_table[protocol].bind;
 	unbind = nl_table[protocol].unbind;
+	release = nl_table[protocol].release;
 	netlink_unlock_table();
 
 	if (err < 0)
@@ -719,6 +719,7 @@ static int netlink_create(struct net *net, struct socket *sock, int protocol,
 	nlk->module = module;
 	nlk->netlink_bind = bind;
 	nlk->netlink_unbind = unbind;
+	nlk->netlink_release = release;
 out:
 	return err;
 
@@ -763,6 +764,8 @@ static int netlink_release(struct socket *sock)
 	 * OK. Socket is unlinked, any packets that arrive now
 	 * will be purged.
 	 */
+	if (nlk->netlink_release)
+		nlk->netlink_release(sk, nlk->groups);
 
 	/* must not acquire netlink_table_lock in any way again before unbind
 	 * and notifying genetlink is done as otherwise it might deadlock
@@ -1402,9 +1405,7 @@ EXPORT_SYMBOL_GPL(netlink_has_listeners);
 
 bool netlink_strict_get_check(struct sk_buff *skb)
 {
-	const struct netlink_sock *nlk = nlk_sk(NETLINK_CB(skb).sk);
-
-	return nlk->flags & NETLINK_F_STRICT_CHK;
+	return nlk_test_bit(STRICT_CHK, NETLINK_CB(skb).sk);
 }
 EXPORT_SYMBOL_GPL(netlink_strict_get_check);
 
@@ -1432,6 +1433,8 @@ struct netlink_broadcast_data {
 	int delivered;
 	gfp_t allocation;
 	struct sk_buff *skb, *skb2;
+	int (*tx_filter)(struct sock *dsk, struct sk_buff *skb, void *data);
+	void *tx_data;
 };
 
 static void do_one_broadcast(struct sock *sk,
@@ -1448,7 +1451,7 @@ static void do_one_broadcast(struct sock *sk,
 		return;
 
 	if (!net_eq(sock_net(sk), p->net)) {
-		if (!(nlk->flags & NETLINK_F_LISTEN_ALL_NSID))
+		if (!nlk_test_bit(LISTEN_ALL_NSID, sk))
 			return;
 
 		if (!peernet_has_id(sock_net(sk), p->net))
@@ -1481,10 +1484,17 @@ static void do_one_broadcast(struct sock *sk,
 		netlink_overrun(sk);
 		/* Clone failed. Notify ALL listeners. */
 		p->failure = 1;
-		if (nlk->flags & NETLINK_F_BROADCAST_SEND_ERROR)
+		if (nlk_test_bit(BROADCAST_SEND_ERROR, sk))
 			p->delivery_failure = 1;
 		goto out;
 	}
+
+	if (p->tx_filter && p->tx_filter(sk, p->skb2, p->tx_data)) {
+		kfree_skb(p->skb2);
+		p->skb2 = NULL;
+		goto out;
+	}
+
 	if (sk_filter(sk, p->skb2)) {
 		kfree_skb(p->skb2);
 		p->skb2 = NULL;
@@ -1496,7 +1506,7 @@ static void do_one_broadcast(struct sock *sk,
 	val = netlink_broadcast_deliver(sk, p->skb2);
 	if (val < 0) {
 		netlink_overrun(sk);
-		if (nlk->flags & NETLINK_F_BROADCAST_SEND_ERROR)
+		if (nlk_test_bit(BROADCAST_SEND_ERROR, sk))
 			p->delivery_failure = 1;
 	} else {
 		p->congested |= val;
@@ -1507,8 +1517,12 @@ out:
 	sock_put(sk);
 }
 
-int netlink_broadcast(struct sock *ssk, struct sk_buff *skb, u32 portid,
-		      u32 group, gfp_t allocation)
+int netlink_broadcast_filtered(struct sock *ssk, struct sk_buff *skb,
+			       u32 portid,
+			       u32 group, gfp_t allocation,
+			       int (*filter)(struct sock *dsk,
+					     struct sk_buff *skb, void *data),
+			       void *filter_data)
 {
 	struct net *net = sock_net(ssk);
 	struct netlink_broadcast_data info;
@@ -1527,6 +1541,8 @@ int netlink_broadcast(struct sock *ssk, struct sk_buff *skb, u32 portid,
 	info.allocation = allocation;
 	info.skb = skb;
 	info.skb2 = NULL;
+	info.tx_filter = filter;
+	info.tx_data = filter_data;
 
 	/* While we sleep in clone, do not allow to change socket list */
 
@@ -1552,6 +1568,14 @@ int netlink_broadcast(struct sock *ssk, struct sk_buff *skb, u32 portid,
 	}
 	return -ESRCH;
 }
+EXPORT_SYMBOL(netlink_broadcast_filtered);
+
+int netlink_broadcast(struct sock *ssk, struct sk_buff *skb, u32 portid,
+		      u32 group, gfp_t allocation)
+{
+	return netlink_broadcast_filtered(ssk, skb, portid, group, allocation,
+					  NULL, NULL);
+}
 EXPORT_SYMBOL(netlink_broadcast);
 
 struct netlink_set_err_data {
@@ -1576,7 +1600,7 @@ static int do_one_set_err(struct sock *sk, struct netlink_set_err_data *p)
 	    !test_bit(p->group - 1, nlk->groups))
 		goto out;
 
-	if (p->code == ENOBUFS && nlk->flags & NETLINK_F_RECV_NO_ENOBUFS) {
+	if (p->code == ENOBUFS && nlk_test_bit(RECV_NO_ENOBUFS, sk)) {
 		ret = 1;
 		goto out;
 	}
@@ -1629,10 +1653,7 @@ static void netlink_update_socket_mc(struct netlink_sock *nlk,
 
 	old = test_bit(group - 1, nlk->groups);
 	subscriptions = nlk->subscriptions - old + new;
-	if (new)
-		__set_bit(group - 1, nlk->groups);
-	else
-		__clear_bit(group - 1, nlk->groups);
+	__assign_bit(group - 1, nlk->groups, new);
 	netlink_update_subscriptions(&nlk->sk, subscriptions);
 	netlink_update_listeners(&nlk->sk);
 }
@@ -1643,7 +1664,7 @@ static int netlink_setsockopt(struct socket *sock, int level, int optname,
 	struct sock *sk = sock->sk;
 	struct netlink_sock *nlk = nlk_sk(sk);
 	unsigned int val = 0;
-	int err;
+	int nr = -1;
 
 	if (level != SOL_NETLINK)
 		return -ENOPROTOOPT;
@@ -1654,14 +1675,12 @@ static int netlink_setsockopt(struct socket *sock, int level, int optname,
 
 	switch (optname) {
 	case NETLINK_PKTINFO:
-		if (val)
-			nlk->flags |= NETLINK_F_RECV_PKTINFO;
-		else
-			nlk->flags &= ~NETLINK_F_RECV_PKTINFO;
-		err = 0;
+		nr = NETLINK_F_RECV_PKTINFO;
 		break;
 	case NETLINK_ADD_MEMBERSHIP:
 	case NETLINK_DROP_MEMBERSHIP: {
+		int err;
+
 		if (!netlink_allowed(sock, NL_CFG_F_NONROOT_RECV))
 			return -EPERM;
 		err = netlink_realloc_groups(sk);
@@ -1681,61 +1700,38 @@ static int netlink_setsockopt(struct socket *sock, int level, int optname,
 		if (optname == NETLINK_DROP_MEMBERSHIP && nlk->netlink_unbind)
 			nlk->netlink_unbind(sock_net(sk), val);
 
-		err = 0;
 		break;
 	}
 	case NETLINK_BROADCAST_ERROR:
-		if (val)
-			nlk->flags |= NETLINK_F_BROADCAST_SEND_ERROR;
-		else
-			nlk->flags &= ~NETLINK_F_BROADCAST_SEND_ERROR;
-		err = 0;
+		nr = NETLINK_F_BROADCAST_SEND_ERROR;
 		break;
 	case NETLINK_NO_ENOBUFS:
+		assign_bit(NETLINK_F_RECV_NO_ENOBUFS, &nlk->flags, val);
 		if (val) {
-			nlk->flags |= NETLINK_F_RECV_NO_ENOBUFS;
 			clear_bit(NETLINK_S_CONGESTED, &nlk->state);
 			wake_up_interruptible(&nlk->wait);
-		} else {
-			nlk->flags &= ~NETLINK_F_RECV_NO_ENOBUFS;
 		}
-		err = 0;
 		break;
 	case NETLINK_LISTEN_ALL_NSID:
 		if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_BROADCAST))
 			return -EPERM;
-
-		if (val)
-			nlk->flags |= NETLINK_F_LISTEN_ALL_NSID;
-		else
-			nlk->flags &= ~NETLINK_F_LISTEN_ALL_NSID;
-		err = 0;
+		nr = NETLINK_F_LISTEN_ALL_NSID;
 		break;
 	case NETLINK_CAP_ACK:
-		if (val)
-			nlk->flags |= NETLINK_F_CAP_ACK;
-		else
-			nlk->flags &= ~NETLINK_F_CAP_ACK;
-		err = 0;
+		nr = NETLINK_F_CAP_ACK;
 		break;
 	case NETLINK_EXT_ACK:
-		if (val)
-			nlk->flags |= NETLINK_F_EXT_ACK;
-		else
-			nlk->flags &= ~NETLINK_F_EXT_ACK;
-		err = 0;
+		nr = NETLINK_F_EXT_ACK;
 		break;
 	case NETLINK_GET_STRICT_CHK:
-		if (val)
-			nlk->flags |= NETLINK_F_STRICT_CHK;
-		else
-			nlk->flags &= ~NETLINK_F_STRICT_CHK;
-		err = 0;
+		nr = NETLINK_F_STRICT_CHK;
 		break;
 	default:
-		err = -ENOPROTOOPT;
+		return -ENOPROTOOPT;
 	}
-	return err;
+	if (nr >= 0)
+		assign_bit(nr, &nlk->flags, val);
+	return 0;
 }
 
 static int netlink_getsockopt(struct socket *sock, int level, int optname,
@@ -1802,7 +1798,7 @@ static int netlink_getsockopt(struct socket *sock, int level, int optname,
 		return -EINVAL;
 
 	len = sizeof(int);
-	val = nlk->flags & flag ? 1 : 0;
+	val = test_bit(flag, &nlk->flags);
 
 	if (put_user(len, optlen) ||
 	    copy_to_user(optval, &val, len))
@@ -1979,9 +1975,9 @@ static int netlink_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
 		msg->msg_namelen = sizeof(*addr);
 	}
 
-	if (nlk->flags & NETLINK_F_RECV_PKTINFO)
+	if (nlk_test_bit(RECV_PKTINFO, sk))
 		netlink_cmsg_recv_pktinfo(msg, skb);
-	if (nlk->flags & NETLINK_F_LISTEN_ALL_NSID)
+	if (nlk_test_bit(LISTEN_ALL_NSID, sk))
 		netlink_cmsg_listen_all_nsid(sk, msg, skb);
 
 	memset(&scm, 0, sizeof(scm));
@@ -2058,7 +2054,7 @@ __netlink_kernel_create(struct net *net, int unit, struct module *module,
 		goto out_sock_release;
 
 	nlk = nlk_sk(sk);
-	nlk->flags |= NETLINK_F_KERNEL_SOCKET;
+	set_bit(NETLINK_F_KERNEL_SOCKET, &nlk->flags);
 
 	netlink_table_grab();
 	if (!nl_table[unit].registered) {
@@ -2069,6 +2065,7 @@ __netlink_kernel_create(struct net *net, int unit, struct module *module,
 		if (cfg) {
 			nl_table[unit].bind = cfg->bind;
 			nl_table[unit].unbind = cfg->unbind;
+			nl_table[unit].release = cfg->release;
 			nl_table[unit].flags = cfg->flags;
 		}
 		nl_table[unit].registered = 1;
@@ -2192,7 +2189,7 @@ static int netlink_dump_done(struct netlink_sock *nlk, struct sk_buff *skb,
 	nl_dump_check_consistent(cb, nlh);
 	memcpy(nlmsg_data(nlh), &nlk->dump_done_errno, sizeof(nlk->dump_done_errno));
 
-	if (extack->_msg && nlk->flags & NETLINK_F_EXT_ACK) {
+	if (extack->_msg && test_bit(NETLINK_F_EXT_ACK, &nlk->flags)) {
 		nlh->nlmsg_flags |= NLM_F_ACK_TLVS;
 		if (!nla_put_string(skb, NLMSGERR_ATTR_MSG, extack->_msg))
 			nlmsg_end(skb, nlh);
@@ -2321,8 +2318,8 @@ int __netlink_dump_start(struct sock *ssk, struct sk_buff *skb,
 			 const struct nlmsghdr *nlh,
 			 struct netlink_dump_control *control)
 {
-	struct netlink_sock *nlk, *nlk2;
 	struct netlink_callback *cb;
+	struct netlink_sock *nlk;
 	struct sock *sk;
 	int ret;
 
@@ -2357,8 +2354,7 @@ int __netlink_dump_start(struct sock *ssk, struct sk_buff *skb,
 	cb->min_dump_alloc = control->min_dump_alloc;
 	cb->skb = skb;
 
-	nlk2 = nlk_sk(NETLINK_CB(skb).sk);
-	cb->strict_check = !!(nlk2->flags & NETLINK_F_STRICT_CHK);
+	cb->strict_check = nlk_test_bit(STRICT_CHK, NETLINK_CB(skb).sk);
 
 	if (control->start) {
 		cb->extack = control->extack;
@@ -2402,7 +2398,7 @@ netlink_ack_tlv_len(struct netlink_sock *nlk, int err,
 {
 	size_t tlvlen;
 
-	if (!extack || !(nlk->flags & NETLINK_F_EXT_ACK))
+	if (!extack || !test_bit(NETLINK_F_EXT_ACK, &nlk->flags))
 		return 0;
 
 	tlvlen = 0;
@@ -2474,7 +2470,7 @@ void netlink_ack(struct sk_buff *in_skb, struct nlmsghdr *nlh, int err,
 	 * requests to cap the error message, and get extra error data if
 	 * requested.
 	 */
-	if (err && !(nlk->flags & NETLINK_F_CAP_ACK))
+	if (err && !test_bit(NETLINK_F_CAP_ACK, &nlk->flags))
 		payload += nlmsg_len(nlh);
 	else
 		flags |= NLM_F_CAPPED;